This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. We continue to conduct research at our permanent field site in the Ivory Coast's Tai National Park. This has been challenging, and core support from Yerkes has been critical. During 2010 Dr. Joyce Cohen met with Dr. McGraw at the site to undertake additional evaluations. Our field assistants continue to collect basic information on the behavioral ecology of the seven cercopithecid species ranging within the core study area of the Tai Monkey Project. These species are Colobus polykomos, Procolobus badius, P. verus, Cercopithecus Diana, C. campbelli, C. petaurista, and Cercocebus atys. Our emphasis has been on more detailed investigation into the ranging behavior, reproductive strategies, and feeding ecology of the sooty mangabey group. Information on most aspects of diet, feeding, and foraging behavior were collected o the approximately 115 members of the group, along with fecal samples for assessment of SIV infection levels. We intend to conduct similar studies on the colobine and guenon species at Tai using new field data and existing skeletal samples.